So much about the Mumbai tragedy was traumatic — from its excruciatingly long duration and cruel fixation on soft targets, to its ruthless efficiency and chillingly novel approach. Some Indians describe it as their 9/11.One decade later, the Mumbai attacks continue to cast a long shadow over India — and the world.For India, the attacks shattered the last great opportunity to pursue peace with arch-rival Pakistan. In 2007, promising back-channel negotiations — launched several years earlier and encouraged by Pakistani President Pervez Musharraf and Indian Prime Minister Manmohan Singh — had gained steam. The negotiations focused on Kashmir — the territorial dispute at the heart of India-Pakistan tensions. However, late in 2007 and then in early 2008, domestic politics in both countries got in the way, and the talks floundered. The mayhem in Mumbai — orchestrated by attackers associated with Lashkar-e-Tayyiba (LeT), a Pakistani terror group with ties to Pakistani intelligence — exploded any hopes of regaining momentum to resume the negotiations. Though the two sides have made modest progress on trade and other low-hanging fruit over the last decade, bilateral ties have improved little. Pakistan's lack of robust legal action against the Mumbai attack organizers constitutes one of the biggest obstacles to regaining more bilateral trust and sustaining dialogue. Additionally, the Mumbai attacks intensified the anti-Muslim and anti-Pakistan rhetoric often heard in India during electoral campaigns — and which the current ruling party, the Hindu nationalist BJP, may use to rally its base in advance of elections next year. Mumbai also exposed India's sea-based security vulnerabilities, prompting New Delhi to step up maritime security enhancements that now constitute a major component of its overall military modernization effort. The Mumbai attackers hijacked a fishing boat, killed four crew members, and sailed in to the city. This came 15 years after explosives arrived in the port city by ship and were used to build bombs that killed 257 people on March 12, 1993. After the 2008 attack, Indian policymakers moved quickly. In 2009, they announced plans to build 100 warships over the next decade. They eventually developed a new three-tiered maritime security system involving maritime police, the coast guard, and the navy. They introduced major technology upgrades, including coastal surveillance radars and undersea sensors. And the coast guard increased its fleet from 74 to 134 vessels. These maritime modernization efforts don't only address sea-based security vulnerabilities. They also help further two key Indian strategic objectives: Keeping pace with rival China's growing maritime power, and pursuing and protecting sea-based energy assets. From a global perspective, the Mumbai attacks established a terrifying new template for terror — one that al-Qaeda and ISIS would often replicate in subsequent years. The blueprint is simple: Small bands of heavily armed assassins staging coordinated attacks on soft targets in urban spaces. The examples proliferate. In 2013, militants stormed a shopping mall in Nairobi and bombers targeted the Boston Marathon. In 2015, gunmen besieged a concert hall, a sports stadium, and restaurants in Paris. And in 2016, assailants attacked the airport and a metro station in Brussels, and jihadists attacked a cafe in Dhaka. Additionally, potential Mumbai-style attacks in Copenhagen and Madrid were foiled in 2009 and 2015, respectively.Counterterrorism officials immediately recognized Mumbai's significance and how easy it would be to pull off elsewhere. It was, in the words of a former counterintelligence official for the New York City Police Department, "a watershed moment for counterterrorism." Just days after the tragedy, New York and Boston authorities staged exercises and trainings to prepare for Mumbai-modeled attacks. After the Paris attack, then British Prime Minister David Cameron said that since Mumbai, "we have all been working together to ensure we could respond to such an attack." Still, anticipating Mumbai-inspired attacks doesn't mean they'll be averted, and especially when they involve simple weaponry and can exploit the open access afforded by major cities in the West and beyond.Perhaps the biggest legacy of Mumbai is plain fear. No matter where in a city one may be — relaxing at the beach, taking in a ball game or concert, strolling on a downtown boulevard, sitting in a café, arriving at the airport — you can never assume you're safe. In the post-Mumbai era, these venues have all been attacked — and could be again. Fortunately, al-Qaeda and especially ISIS, the most potent practitioners of these Mumbai-modeled attacks, have become shadows of their former selves. Still, any ragtag group of unaffiliated radicals can easily muster the capacity to wreak havoc with handguns, crude bombs, or even vehicles — and in cities far from the one that spawned such a tragic precedent 10 years ago.